A sequential gas turbine installation, as emerges for example from EP 0 620 362 B1, has a high-pressure gas turbine which is acted upon by the hot gases of a high-pressure combustion chamber arranged upstream. Upstream of this high-pressure combustion chamber, a compressor ensures the provision of the compressor air. Downstream of the high-pressure gas turbine, a low-pressure combustion chamber is provided. The hot gases of this low-pressure combustion chamber act on a low-pressure gas turbine arranged downstream. Such a gas turbine installation is preferably operated using a common rotor which carries the rotor blades of the compressor, of the high-pressure gas turbine and of the low-pressure gas turbine.
Such a gas turbine installation uses a carrier ring of the type mentioned in the introduction in the region of the high-pressure gas turbine, in order to carry guide vanes and/or heat shields of the high-pressure gas turbine, or to position these in the gas path. In that context, the carrier ring can carry guide vanes of the high-pressure gas turbine which are operatively connected to the rotor blades of the high-pressure gas turbine. In addition, the carrier ring can also carry heat shields between guide vanes which are adjacent in the circumferential direction. Alternatively, the carrier ring can also be used to carry heat shields which are radially adjacent to rotor blades of the high-pressure gas turbine and lie in the same axial plane.
Within the context of mounting such a gas turbine, it is in principle possible to push the preassembled carrier ring axially onto the rotor, which is already fitted with the guide vanes for the compressor and the two gas turbines. In the correct axial position, the carrier ring can, for further assembly, be secured to the rotor with the aid of retaining elements as mounting aid. The rotor, together with the carrier ring, may then be placed in a stator casing in the gas turbine installation. Furthermore, the carrier ring may then be attached to the stator casing.
The retaining elements, which have permitted the carrier ring to be secured to the rotor for assembly, are then removed again. Such a procedure is relatively onerous. Furthermore, the axial length of the rotor blading of the compressor and/or of the low-pressure gas turbine is limited by the free diameter of the carrier ring in order that the carrier ring might be pushed onto the bladed rotor. Finally, maintenance work for exchanging the guide vanes and/or the heat shields of the carrier ring proves to be most onerous as the entire rotor must be removed from the stator casing in order to be able to take off the carrier ring again. In such a gas turbine installation, the carrier ring is often also termed the High-Pressure Turbine (HPT) ring.
DE 199 50 108 A1 discloses a heat-shield ring which is arranged in a gas turbine, radially adjacent to rotor blades of the gas turbine. The disclosed heat-shield ring comprises a plurality of heat-shield segments which are arranged one behind the other in the circumferential direction and which are held with the aid of clamping segments attached to the stator casing. The clamping segments are arranged axially on the stator casing on either side of the heat-shield segments and each have, on their inner sides facing one another in the axial direction, a groove which extends in the circumferential direction and in which the heat-shield segments engage axially on the peripheral side.
WO 2010/040339 A1 discloses a rotor blade ring for a rotor of a gas turbine, consisting of a multiplicity of circumferentially adjacent rotor blades. A circumferentially segmented assembly ring is provided for assembling the rotor blade ring, where suitable connecting pieces are provided in order to connect circumferentially adjacent ring segments. The use of such a segmented mounting aid simplifies the introduction of a prestress in the guide vane ring.